When using dental floss for flossing a person's teeth, it is the common practice to insert the floss between two adjacent teeth by supporting and pulling taut a floss strand either with the person's fingers or with a tool such as disclosed in my U.S. Letters Patent 3,799,177 and then sliding the floss between the teeth from the top edge thereof. However, when a person has a permanent bridge it is not possible to slide the floss between the supporting teeth. Also, in some instances a person may have two teeth that are too close together to permit vertical sliding of the floss in and out from between the teeth.